Effect of controlled-release metoprolol on blood pressure and exercise heart rate in hypertension: A comparison with conventional tablets

In a double-blind study with parallel groups a new controlled-release (CR) formulation of metoprolol¹, 100 mg once daily, was compared with conventional metoprolol tablets, 100 mg once daily, in 27 patients with primary hypertension.Exercise tests on a bicycle ergometer were undertaken 24 h after intake of the last dose of the drug following a four-week placebo run-in period and after four weeks of active treatment.